1. Antibiotic Primer Jen Nicol PGY-2 Dr. Sue Kuhn Dr. McPherson May 19, 2011

2. Objectives Review properties of commonly used antibiotics in the ED Discuss Empiric Coverage of common infectious diseases Brief review of resistant organisms Common ID mishaps in the ED

3. The Drugs

4. The Bugs

5. Community Acquired Pneumonia - Pediatrics Paediatr Child Health. 2003:666-619 Alberta Clinical Practice Guideline 2008 Stanford guide 2009

6. Community Acquired Pneumonia - Adults CID 2007:44(Suppl 2) S28-72 (Infectious Diseases Society of America/American Thoracic Society) Can J Infect Dis 2000;11:237-48 (Canadian Infectious Disease Society/Canadian Thoracic Society) Stanford Guide 2009

7. MDR Streptococcus Pneumoniae Age 65 Β-lactam therapy in last 3 months (most predictive) Alcoholism, Immunosuppressive Therapies or illness Medical co-morbidities Exposure to a child in daycare

8. Strep Pneumo Local susceptibilities Penicillin 95% (83-91% 2009) Ceftriaxone 95% Erythromycin 78% SXT 76% Levofloxacin 86% Tetracycline 87%

9. Community Acquired Pneumonia - Adults CID 2007:44(Suppl 2) S28-72 (Infectious Diseases Society of America/American Thoracic Society) Can J Infect Dis 2000;11:237-48 (Canadian Infectious Disease Society/Canadian Thoracic Society) Stanford Guide 2009

10. Acute uncomplicated cystitis and Pyelonephritis CID 2011;52:e103-120 (Infectious Diseases Society of America/European Society for Microbiology and Infectious Diseases) Stanford Guide 2009

11. E-Coli Local Susceptibility Patterns – Amoxicillin 55% – Cephalexin 73% – Cefazolin 94% – Ceftriaxone 97% – TMP-SMX 79% – Ciprofloxacin 94% – Nitrofurantoin 98% – Pip/tazo 98% – Ceftriaxone 97% – TMP-SMX 79% – Ciprofloxacin 94% – Gentamycin 95%

12. Acute Bacterial Meningitis Clinical Microbiology Reviews;2010:467–492 (Infectious Diseases Society of America) Paediatr Child Health;2008:309 (Canadian Paediatric Society)

13. Intra-abdominal Sepsis Can J Infect Dis Med Microbiol. 2010;21:11-37 (Canadian Surgical Society/Association of Medical Microbiology and Infectious Disease Canada) CID 2010;50:133-164 (Guidelines from The Surgical Infection Society and the Infectious Diseases Society of America)

14. Skin and Soft Tissue Infections CID 2005;41:1373-1406 (Infectious Diseases Society of America) CID 2011:52:18-55 (Infectious Diseases Society of America) – update on MRSA

15. Postpartum Endometritis

16. Antibiotics: Pregnancy & Breastfeeding

17. Pseudomonas aeruginosa Favors moist, warm environments Generally an infection of the hospitalized and immunocomprimised Community infections: – hot tub/whirlpools – contact lens use

18. Risk Factors Chronic oral steroid administration Severe underlying bronchopulmonary disease (ie COPD, asthma) Alcoholism Frequent antibiotic therapy Hospitalization

19. Treatment of p. aeruginosa infections Monotherapy vs. combination therapy Theory: to prevent resistance – No definitive consensus – Evidence to suggest non-inferiority Some antibiotics are not as effective as monotherapy (gentamycin)

20. Treatment of p. aeruginosa infections Anti-pseudomonal β-lactam or carbapenem or aztreonoman PLUS aminoglycoside – β-lactam = Ceftazadime, cefepime, pipercillin- tazobactam – Aminoglycoside = gentamycin, tobramycin, amikacin – Carbapenem = imipenem, meropenem, NOT ertapenem (not active against PA)

21. Local Susceptibilities Pipercillin/tazobactam 95% Meropenem 94-99% Ceftazadime 90-95% Ciprofloxacin 91% Gentamycin 89% Tobramycin 96% Calgary Lab Services Antibiogram 2010

22. MRSA: Methicillin Resistant Staphylococcus Aureus First documented resistance in 1950’s, increasing prevalence ever since. Netherlands 2% vs. Japan >70% Mutation of transpeptidase inhibiting binding of penicillins 2 varieties…..

23. Community Acquired MRSA

24. “Little dog big bite” Cause serious soft tissue infections and necrotizing pneumonia which can be rapidly fatal. Much more susceptible to wide range of antibiotic therapy

25. CA-MRSA RF’s native and aboriginal communities sports teams child care centers military personnel men who have sex with men prison inmates and guards Close contact with an MRSA carrier MANY HAVE NO RF’s AT ALL!!!

26. Hospital Acquired MRSA

27. “Big and ever present, need to trip over it to get hurt, but hard to get rid of if he gets a hold of you” More resistant and difficult to treat, but less invasive.

28. HA-MRSA Recent hospitalization or surgery ICU stay Recent antibiotic use Living in a nursing home Carrying an indwelling catheter or device

29. Oral Outpatient Therapy Patient must be systemically well Clindamycin TMP-SMX Doxycycline For improved coverage of β-hemolytic strep, add beta-lactam (amoxicillin) CID 2005;41:1373-1406 (Infectious Diseases Society of America) CID 2011:52:18-55 (Infectious Diseases Society of America) – update on MRSA

30. Inpatient, sick patients IV Vancomycin IV linezolid Daptomycin Rifampin (with vano/linez) Tigecycline ? Double Coverage: MRSA prosthetic valve EI, osteomyelitis, prosthetic joint infection, or septic arthritis CID 2005;41:1373-1406 (Infectious Diseases Society of America) CID 2011:52:18-55 (Infectious Diseases Society of America) – update on MRSA

31. Local Susceptibility Patterns: Clindamycin 72% TMP-SMX 98% Doxycycline 98% Vancomycin 100% Linezolid N/A Gentamycin 100% Penicillin 18% Calgary Lab Services Antibiogram 2010

32. ESBL: Extended Spectrum β-Lactamase producing Gram negative bacteria Resistant to all β-lactam antibiotics except carbapenems and cephamycins Range of enterobactereae – E-Coli, klebsiella most common Traditionally acquired in hospital setting; recent increase in CA-ESBL Bacteremia, SSTI’s, UTI, pneumonia, meningitis….

33. Risk Factors for CA-ESBL > 65 Female > male Functional dependence Admission from long term care Recent hospitalization Bladder catheter Antibiotic use Cefalosporin use CID 2009;49: 682

34. Treatment Piptazo, cefepime, 3 rd generation cephalosporins, quinolones UTI: ? ciprofloxacin Carbapenems – No randomized controlled studies – Most prospective observational experience with meropenem, best survival outcomes

35. Don’t do this… You will make people mad NOT taking ANY or enough cultures before starting antibiotics Treating stable patients with empiric, broad spectrum antibiotics before a clear source is identified (it IS OK to wait!!!!) NOT using netcare to check for previous treatment for resistant organisms in the past

36. Don’t do this… You will make people mad Fever in the returning traveler to HPTP (They belong in medicine clinic!!) Sending joint prosthesis infections to HPTP (DON’T bipass ortho – they will get angry!!) NOT draining fluctuant, juicy abscesses, or arranging diagnostic or surgical interventions before sending patient to HPTP – (this is very difficult to do in high volume outpatient clinic!!!)

37. The End Questions???